SRF2023 - List of Authors (Marks, H.S.)

Paper	Title	Page
MOPMB001	Development and Testing of Split 6 GHz Cavities With Niobium Coatings	51
	N.L. Leicester, G. Burt, H.S. Marks Cockcroft Institute, Lancaster University, Lancaster, United Kingdom E. Chyhyrynets, C. Pira INFN/LNL, Legnaro (PD), Italy J.A. Conlon, O.B. Malyshev, B.S. Sian, R. Valizadeh STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom D.J. Seal Lancaster University, Lancaster, United Kingdom
	Superconducting thin-films on a copper substrate are used in accelerator RF cavities as an alternative to bulk Nb due to the high thermal conductivity of copper and the lower production costs. Although thin-film coated RF cavities can match, or even exceed the performance of bulk Nb, there are some challenges around the deposition. The RF cavities are often produced as two half-cells with a weld across the centre where the RF surface current is highest, which could reduce cavity performance. To avoid this, a cavity can be produced in 2 longitudinally split halves, with the join parallel to the surface current. As the current doesn’t cross the join a simpler weld can be performed far from the fields, simplifying the manufacturing process, and potentially improving the cavities performance. This additionally allows for different deposition techniques and coating materials to be used, as well as easier post-deposition quality control. This paper discusses the development and testing of 6 GHz cavities that have been designed and coated at the Cockcroft Institute, using low temperature RF techniques to characterise cavities with different substrate preparations and coating techniques.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-MOPMB001
About •	Received ※ 18 June 2023 — Revised ※ 22 June 2023 — Accepted ※ 26 June 2023 — Issue date ※ 04 July 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMB011	Deposition and Characterisation of V₃Si films for SRF Applications	84
	C. Benjamin, J.A. Conlon, O.B. Malyshev, R. Valizadeh STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom G. Burt, O.B. Malyshev, D.J. Seal, R. Valizadeh Cockcroft Institute, Warrington, Cheshire, United Kingdom G. Burt, D.J. Seal Lancaster University, Lancaster, United Kingdom N.L. Leicester, H.S. Marks Cockcroft Institute, Lancaster University, Lancaster, United Kingdom L.G.P. Smith STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom
	Funding: This project has received funding from the European Union’s Horizon 2020 Research and Innovation programme under Grant Agreement No 101004730. A15 superconducting materials, like V₃Si and Nb₃Sn, are potential alternatives to Nb for next generation thin film SRF cavities when operated at 4 K. Their relatively high Tc and superconducting properties could allow for higher accelerating gradients and elevated operating temperatures. We present work on the deposition of V₃Si thin films on planar Cu substrates and an open structure 6 GHz cavity, using physical vapour deposition (PVD) and a V₃Si single target. The surface structure, composition and DC superconducting properties of two planar samples were characterised via secondary electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDX) and in a magnetic field penetration facility. Furthermore, the first deposition using PVD of a V₃Si film on a 6 GHz split cavity and the RF performance is presented.
	Poster MOPMB011 [7.496 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-MOPMB011
About •	Received ※ 16 June 2023 — Revised ※ 22 June 2023 — Accepted ※ 29 June 2023 — Issue date ※ 19 July 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Development and Testing of Split 6 GHz Cavities With Niobium Coatings

51

N.L. Leicester, G. Burt, H.S. Marks
Cockcroft Institute, Lancaster University, Lancaster, United Kingdom
E. Chyhyrynets, C. Pira
INFN/LNL, Legnaro (PD), Italy
J.A. Conlon, O.B. Malyshev, B.S. Sian, R. Valizadeh
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
D.J. Seal
Lancaster University, Lancaster, United Kingdom

Superconducting thin-films on a copper substrate are used in accelerator RF cavities as an alternative to bulk Nb due to the high thermal conductivity of copper and the lower production costs. Although thin-film coated RF cavities can match, or even exceed the performance of bulk Nb, there are some challenges around the deposition. The RF cavities are often produced as two half-cells with a weld across the centre where the RF surface current is highest, which could reduce cavity performance. To avoid this, a cavity can be produced in 2 longitudinally split halves, with the join parallel to the surface current. As the current doesn’t cross the join a simpler weld can be performed far from the fields, simplifying the manufacturing process, and potentially improving the cavities performance. This additionally allows for different deposition techniques and coating materials to be used, as well as easier post-deposition quality control. This paper discusses the development and testing of 6 GHz cavities that have been designed and coated at the Cockcroft Institute, using low temperature RF techniques to characterise cavities with different substrate preparations and coating techniques.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-MOPMB001

About •

Received ※ 18 June 2023 — Revised ※ 22 June 2023 — Accepted ※ 26 June 2023 — Issue date ※ 04 July 2023

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMB011

Deposition and Characterisation of V₃Si films for SRF Applications

84

C. Benjamin, J.A. Conlon, O.B. Malyshev, R. Valizadeh
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
G. Burt, O.B. Malyshev, D.J. Seal, R. Valizadeh
Cockcroft Institute, Warrington, Cheshire, United Kingdom
G. Burt, D.J. Seal
Lancaster University, Lancaster, United Kingdom
N.L. Leicester, H.S. Marks
Cockcroft Institute, Lancaster University, Lancaster, United Kingdom
L.G.P. Smith
STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom

Funding: This project has received funding from the European Union’s Horizon 2020 Research and Innovation programme under Grant Agreement No 101004730.
A15 superconducting materials, like V₃Si and Nb₃Sn, are potential alternatives to Nb for next generation thin film SRF cavities when operated at 4 K. Their relatively high Tc and superconducting properties could allow for higher accelerating gradients and elevated operating temperatures. We present work on the deposition of V₃Si thin films on planar Cu substrates and an open structure 6 GHz cavity, using physical vapour deposition (PVD) and a V₃Si single target. The surface structure, composition and DC superconducting properties of two planar samples were characterised via secondary electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDX) and in a magnetic field penetration facility. Furthermore, the first deposition using PVD of a V₃Si film on a 6 GHz split cavity and the RF performance is presented.

Poster MOPMB011 [7.496 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-MOPMB011

About •

Received ※ 16 June 2023 — Revised ※ 22 June 2023 — Accepted ※ 29 June 2023 — Issue date ※ 19 July 2023

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)